Method of separating or extracting bodies from partial oxidation products



Patented Aug. 14, 1934 METHOD OF SEPARATING OR EXTRACTING BODIES FROMPARTIAL OXIDATIQN'.

ERODUCTS Joseph Hidy James, Pittsburgh, Pa, asslgnor to illlarence P.Byrnes, Sewiclxley, Pa trustee No Drawing. Application March 12, 1930,Serial No. 435,375

a claim. (on. Edd-did) In the synthetic manufacture of omrgen-containingaliphatic hydrocarbons, a liquid mixture of several difierent classes ofbodies in the range from alcohols to oxygenated organic acids isohtained, each class being present in a range of different molecularweights. Hence, this liquid mixture is of unusual complexity and it hasbeen a matter of great dificulty to extract or separate a class orclasses of bodies therefrom in obtaining industrial products. Forexample, in my vapor or gaseous phase partial oxidation process, whereinhydrocarbon is mixed with an oxygen containinggas and passed through ahot reaction zone, preferably in contact with a catalyst, at atemperature below that of continuous sellsustained complete combustion,both the products condensed and collected in the scrubbers are of greatcomplexity including more highly oxidized and less highly oxidizedbodies each of difierent molecular weights.

The present invention relates to the extraction from such mixtures ofdifierent bodies or classes of bodies or the separation of the mixtureinto different classes of bodies. I have found that such extraction canbe effected by the use of liquid sulphur dioxide at relatively lowtemperatures. I am aware of the-Edeleanu process of refining petroleumoils, in which instead of employing sulphuric acid in such refining,liquid S02 is used to remove aromatic unsaturated and other industrialhydrocarbons.

. My process does not relate to the treatment of hydrocarbons, but tothe treatment of liquid mixtures containing material proportions ofoxygen-containing hydrocarbons and to the separation of certain bodiestherefrom at relatively low temperatures. lhe main object of myinvention lies in the extraction of the more highly oxidized bodies fromthe less highly oxidized bodies in the liquid mixture by careful controlof treatment with S02 at temperatures below those allowinghydrocarbonsolubility; but it is also possible by regulating and controlling thetemperature to extract the oxidized bodies with the contained olefinsand aromatics in one operation. Solubility of such hydrocarbons andtheir oxidized derivatives increases with, temperature, and hence ameans is affordedof cflecting fractional extraction by carefulregulation or control of temperature. Liquid sulphur dioxide boils underatmospheric pressure at about 8 0., and hence, if the extraction is atatmospheric pressure, it should be carried on below that temperature.

In the following examples, the pressure was atmospheric and thetemperature was held at -l8 to 2ii by suitable freezhig mixtures.

Example I A partially oxidized gasoline subsequently thermolized ordecomposed at about i530" 'C. over alumina was taken as the mixture totreat. This was cooled to -18 0. and one and onehalf volumes of liquidsulphur dioxide for each volume "of oxidation mixture added. Layers wereformed and the lower layer containing liquid S02 drawn-on and the =SO:allowed to evaporate by a rise in temperature. This gave an extract ofthe more highly oxidized bodies to an amount of 68%, leaving adifierence of W 32%' by volume of the paramn series and naphthenebodies. A. careful chemical analysis of the original product treatedshowed 46.6%

by volume of oxidized bodies, olefins and terpenes; l9.t%. by volume ofaromatics and i5 33.6% by volume of substantially unchanged hydrocarbonsof the paramn and naphthene series.

Hence, it is apparent that the above extraction gave a nearly completeseparation from the parafiin and naphthene bodies of the other bodiespresent. I

Example If A partially oxidized gasoline which had been treated by myvapor phase oxidation process was taken, its analysis showing 39% byvolume of oxidized bodies and olefins; 6.6% by volume of aromatics, and54.4% by volume of membersof the'paraflln and naphthene series.

A liquid'sulphur dioxide extraction carried out at low temperaturesubstantially similar to that of Example I showed from the lower layer,

after evaporation of the sulphur dioxide, 44% of oxidized bodies,olefins and aromatics leaving 56% for the members of the paraffin andnaphthene series; this again being substantially in accord with theresults of analysis of the material thus extracted.

, From the separated mixture containing oxidized bodies, olefins andaromatics, the oxidized bodies may be separated by regulated treatmentwith diluted ethyl alcohol or. isopropyl alcohol, as set forth forexample in my United States Patents Nos. 1,782,963 and 1,782,964,granted November 25, 1930. As therein set forth," alcohol diluted todifferent degrees of strength acts to separate more highly oxidized fromless highly oxidized bodies in the product. The degree of dilutionafiects the degree of solubility.

Mid

. In the present liquid SO: process, the order of extraction will be,first the acids; next the aldehydes and next the alcohols. 'In otherwords, from the more highly oxidized to the less highly oxidizedcompounds. Hence to extract the more highly oxidized bodies and toremove the oxidized bodies only, the treatment must be carried out attemperatures below which two or three active hydrocarbon groups, such asolefins,

aromatics and terpenes, dissolve in the liquid sulphur dioxide.

' Therefore, by careful regulation and control of the temperature thesebodies may be separated from each other in the extraction, and severaldifferent classes of bodies obtained under difierent temperatures allbelow the boiling point of the liquid sulphur dioinde. .01 course, ineach case the sulphur dioxide is distilled off and recovered in a closedsystem, the same as in the Edeleanu process.

In order to make these separations of the diflerent classes of bodies,the temperatures must be carried down to 45 C. and lower, and we mustalso regulate carefully the addition of the liquid sulphur dioxide inorder to accomplish the gradation desired in the products removed.

It will be understood that the Edeleanu system or plant apparatus may beemployed with the heat recovered, S02 recovered, etc., as now well knownin that process.

Many changes may be made in the form of apparatus employed, in thetemperatures used and other parts of the process without depart ing frommy invention.

I claim:

1. In the process of separating the more highly oxidized bodies from theless highly oxidized bodies of a liquid mixture containing oxygenderivatives of hydrocarbons in the range from alcohols to orwgenatedorganic acids, the steps consisting of treating the same with liquidsuling point, varying the temperature during the extraction to obtainfractional extraction, and recovering sulphur dioxide.

3. In the process of separating the more highly oxidized bodies from theless highly highly oxidized bodies from the less highly oxidized bodiesof a liquid mixture containing oxygen derivatives of hydrocarbons in therange from alcohols to oxygenated organic acids, the

steps consisting of treating the same with liquid sulphur dioxide at atemperature below its boiling point, and then treating an extractedportion containing oxygen derivatives with dilute alcohol to furtherseparate bodies of difierent degrees of oxidation therein.

5. As a new composition of matter, Edeleanu extract of a partiallyoxidized petroleum fraction, said extract containing the more highlyoxidized bodies and a reduced and relatively small proportion of lesshighly oxidized bodies.

6. In the process of separating the more highly oxidized bodies from theless highly oxidized bodies of a liquid mixture containing oxygenderivatives of hydrocarbons in the range from alcohols to oxygenatedorganic acids, the step consisting in treating the same with liquidsulphur dioxide at a temperature below its boiling point and to anamount sufficient to dissolve the more highly oxidized compounds butinsuiiicient to dissolve all'of the oxidized compounds.

7. In the process of separating the more highly oxidized bodies from theless highly oxidized bodies of a liquid mixture containing oxygenderivatives of hydrocarbons in the range from alcohols to oxygenatedorganic acids, the steps consisting of treating the same with liquidsulphur dioxide at a temperature below its boiling point, and separatingandremoving the more highly oxidized compounds from the less highlyoxidized compounds.

. JOSEPH HIDY JAMES.

